2. Chemistry of Living Systems Living Systems

3. Strucure of Atoms Atom: smallest unit of matter Three components of an atom are…  Electrons -1  Protons +1  Neutrons 0 Found outside the nucleus Found in the nucleus

4. Ions= Different # of p + and e - ISOTOPES= Same # of p + and e - Different # of n 0 Atomic Weight = p + + n 0 Atomic Number= # of Protons 11 Na ATOMS

5. Count the electrons! # of electrons in the outer shell are clues! # of electrons in the outer shell are clues! Greater than 4 e- in the outer shell will take or share with other atoms (nonmetals) Greater than 4 e- in the outer shell will take or share with other atoms (nonmetals) Less than 4 e- in the outer shell will give to other atoms (metals) Less than 4 e- in the outer shell will give to other atoms (metals) Provides hints on how and what types of bonds form Provides hints on how and what types of bonds form

6. Isotopes Versions of the same element – but have different numbers of neutrons (N) Versions of the same element – but have different numbers of neutrons (N) Z= number of protons (P) A=N+Z

7. Elements Essential to Life About 25 elements are essential to living organisms About 25 elements are essential to living organisms CHNOPS: Make up 97% of living matter CHNOPS: Make up 97% of living matter

8. Natural Elements in the Human Body ELEMENTS ATOMIC # % in HUMANS Oxygen (O)865.0 Carbon (C) 618.5 Hydrogen (H) 19.5 Nitrogen (N) 73.3 Calcium (Ca) 201.5 Phosphorus (P) 151.0 Potassium (K) 190.4 Sulfur (S) 160.3 Sodium (Na) 110.2 Magnesium (Mg) 120.2 Chlorine (Cl) 170.1

9. Chemical Bonds Chemical Bonds are the attractive force that hold atoms together in a molecule Bonds form when electrons are shared OR transferred between atoms Covalent bonds – sharing electrons (“co-” means to share as in cooperate) Covalent bonds – sharing electrons (“co-” means to share as in cooperate) Ionic Bonds – give and take electrons Ionic Bonds – give and take electrons Hydrogen Bonds – weak attractions between molecules Hydrogen Bonds – weak attractions between molecules Stronger atoms try to “steal” the H’s electron, but it keeps a tiny hold on it.

10. Nonpolar Covalent Bonds Electrons are shared equally Electrons are shared equally

11. Polar Covalent Bonds Share electrons as in other covalent bonds, but the nucleus of one atom attracts the electrons more strongly so it is not equal. Share electrons as in other covalent bonds, but the nucleus of one atom attracts the electrons more strongly so it is not equal.

12. Ionic Bonding One atom gets extra electron(s) (becomes a negative ion) and one gives extra electron(s) (becomes a positive ion) the two ions attract each other. One atom gets extra electron(s) (becomes a negative ion) and one gives extra electron(s) (becomes a positive ion) the two ions attract each other.

14. Hydrogen Bond When water molecules are close together, their positive and negative regions are attracted to the oppositely- charged regions of nearby molecules. When water molecules are close together, their positive and negative regions are attracted to the oppositely- charged regions of nearby molecules. The force of attraction, shown here as a dotted line, is called a hydrogen bond. The force of attraction, shown here as a dotted line, is called a hydrogen bond. The hydrogen bond has only 5% or so of the strength of a covalent bond. The hydrogen bond has only 5% or so of the strength of a covalent bond.

15. CARBON Why is carbon so important in biological molecules? Why is carbon so important in biological molecules? Carbon forms 4 covalent bonds giving it the ability to create massive molecular chains. Molecules with carbon are called ORGANIC Molecules without carbon are called INORGANIC

16. What are the important molecules of life?

18. Properties of Water Movie

19. The Structure of Water “V” shaped molecule “V” shaped molecule Unequal sharing of electrons causes oxygen to have a slightly negative charge Unequal sharing of electrons causes oxygen to have a slightly negative charge called a polar molecule called a polar molecule

20. Properties of Water Cohesion is the tendency of molecules of the same kind to stick to one another. Cohesion is the tendency of molecules of the same kind to stick to one another. Water has stronger cohesion than most liquids Water has stronger cohesion than most liquids

21. Water molecules are also attracted to certain other molecules Water molecules are also attracted to certain other molecules Attraction between unlike molecules is called adhesion Attraction between unlike molecules is called adhesion

22. Cohesion pulls molecules at the surface tightly together, forming a film-like boundary Cohesion pulls molecules at the surface tightly together, forming a film-like boundary This is surface tension This is surface tension

24. Walking on Water

25. Carbohydrates (C,H, and O molecules in a ratio of 1:2:1) Carbohydrates are an important energy source for cells. Carbohydrates are an important energy source for cells.

27. TYPES OF CARBOHYDRATES Monosaccharide – simple sugars made of one sugar molecule. (ex. Glucose)

28. TYPES OF CARBOHYDRATES Disaccharides – (ex. Sucrose) Disaccharides – (ex. Sucrose) 2 monosaccharides linked together

29. Polysaccharides – ex. Starch, Cellulose) Polysaccharides – ex. Starch, Cellulose) More than two sugars linked together. TYPES OF CARBOHYDRATES

30. Did you notice how the sugars all sound the same? They all end in “-ose” (-ose = sugar) They all end in “-ose” (-ose = sugar) Ex. Sucrose, Glucose, Fructose, Lactose Ex. Sucrose, Glucose, Fructose, Lactose

31. TYPES OF CARBOHYDRATES Simple Carbs ~ mono and disaccahrides Simple Carbs ~ mono and disaccahrides Complex carbs ~ starches, polysaccharides Complex carbs ~ starches, polysaccharides

32. LIPIDS Contain C,H,O,N, -P Phospholipids: Made up of two parts: A head (it is hydrophillic) A head (it is hydrophillic) A tail made of a hydrocarbon chain (it is hydrophobic). A tail made of a hydrocarbon chain (it is hydrophobic). This lets the lipids form bilayers creating waterproof barriers like in a cell’s membrane. This lets the lipids form bilayers creating waterproof barriers like in a cell’s membrane.

33. LIPIDS Fatty acids, waxes, fats, steroids and oils are lipids (all are insoluble in water) Fatty acids, waxes, fats, steroids and oils are lipids (all are insoluble in water)

34. Steroids and Cholesterol Steroids include such well known compounds as cholesterol, sex hormones, birth control pills, cortisone, and anabolic steroids. Steroids include such well known compounds as cholesterol, sex hormones, birth control pills, cortisone, and anabolic steroids.

35. Cholesterol The best known and most abundant steroid in the body is cholesterol. The best known and most abundant steroid in the body is cholesterol. It is the major compound found in gallstones and bile salts. Cholesterol also contributes to the formation of deposits on the inner walls of blood vessels. It is the major compound found in gallstones and bile salts. Cholesterol also contributes to the formation of deposits on the inner walls of blood vessels.

36. Proteins Molecules made up of one or more chains of amino acids. They are used for many functions… Molecules made up of one or more chains of amino acids. They are used for many functions… Include the elements CHNOS Include the elements CHNOS

37. Proteins are used for… Structure – they make collagen in skin and keratin in hair/nails/horn Structure – they make collagen in skin and keratin in hair/nails/horn

38. Proteins are used for… Movement ~ actin and myosin in muscle stimulate the muscle to move Movement ~ actin and myosin in muscle stimulate the muscle to move

39. Proteins are used for… Defense ~ antibodies in bloodstream Defense ~ antibodies in bloodstream

40. Proteins are used for… Storage ~ ex. corn seed coats are predominately made of protein Storage ~ ex. corn seed coats are predominately made of protein

41. Proteins are used for… Receiving signals- proteins embedded in the plasma membrane will serve as active gates into and out of the cell (for specific substances). Receiving signals- proteins embedded in the plasma membrane will serve as active gates into and out of the cell (for specific substances).

42. Nucleic Acids Nucleic Acids (used in DNA or RNA) – long chains of pieces called nucleotides. A nucleotide has 3 parts… Nucleic Acids (used in DNA or RNA) – long chains of pieces called nucleotides. A nucleotide has 3 parts… 1. five carbon sugar (ribose or deoxyribose) 2. phosphate group 3. Nitrogen base (A,T,C or G) Includes the elements CHNOP Includes the elements CHNOP

43. Chemical Reactions Reactants and Products  A chemical reaction is the process by which atoms or groups of atoms in substances are reorganized into different substances.  Clues that a chemical reaction has taken place include the production of heat or light, and formation of a gas, liquid, or solid. Chemical reaction Physical reaction

44. Chemical Reactions Chemical Equations  Chemical formulas describe the substances in the reaction and arrows indicate the process of change.  Reactants are the starting substances, on the left side of the arrow.  Products are the substances formed during the reaction, on the right side of the arrow.

45. Chemical Reactions  Glucose and oxygen react to form carbon dioxide and water.

46. Chemical Reactions  The activation energy is the minimum amount of energy needed for reactants to form products in a chemical reaction. Energy of Reactions

47. Chemical Reactions  This reaction is exothermic and released heat energy.  The energy of the product is lower than the energy of the reactants.

48. Chemical Reactions  This reaction is endothermic and absorbed heat energy.  The energy of the products is higher than the energy of the reactants.

49. Chemical Reactions  A catalyst is a substance that lowers the activation energy needed to start a chemical reaction.  Enzymes are biological catalysts.  It does not increase how much product is made and it does not get used up in the reaction. Enzymes

50. Enzymes

51. So what is an Enzyme? An enzyme is used to speed things up or help break things down in your body.

52. Words You Should Know Enzyme (E): protein catalyst Enzyme (E): protein catalyst Catalysts: speed up reactions without being changed by the reaction Catalysts: speed up reactions without being changed by the reaction Substrate (S): reactant(s) in the enzyme-catalyzed reaction Substrate (S): reactant(s) in the enzyme-catalyzed reaction Active site: area of enzyme where substrate(s) bind(s) Active site: area of enzyme where substrate(s) bind(s)

53. Enzymes Enzymes are proteins with a SPECIFIC SHAPE Enzymes are proteins with a SPECIFIC SHAPE The active site is a part of the protein which recognizes and binds to the substrate The active site is a part of the protein which recognizes and binds to the substrate Cofactors (e.g. Zn 2+, Cu 2+, B vitamins) some enzymes won’t hook-up to a substrates without these Cofactors (e.g. Zn 2+, Cu 2+, B vitamins) some enzymes won’t hook-up to a substrates without these

54. How do enzymes speed up reactions? Enzymes lower the activation energy (E A =amount of energy that reactant molecules require to start a reaction)

55. Enzymes Are involved in every biochemical reaction and thereby control metabolism Are involved in every biochemical reaction and thereby control metabolism Are named according to the reaction that they facilitate Examples: Sucrase breaks down sucrose into glucose and fructose Are named according to the reaction that they facilitate Examples: Sucrase breaks down sucrose into glucose and fructose DNA Polymerase helps build DNA polymers DNA Polymerase helps build DNA polymers

56. Enzymes

57. Did you notice that enzyme all sound the same? All enzymes end in “-ase” All enzymes end in “-ase” DNA Polymerase DNA Polymerase Sucrase Sucrase

58. Factors affecting enzyme activity 1. TEMPERATURE 2. Concentration of Enzyme 3. Concentration of Substrate 4. pH 5. Inhibitors

59. pH pH is the measure of the acidity or alkalinity of a solution pH is the measure of the acidity or alkalinity of a solution Specifically it is a measurement of the concentration of H + ions in a solution Specifically it is a measurement of the concentration of H + ions in a solution The concentration of hydrogen ions is commonly expressed in terms of the pH scale The concentration of hydrogen ions is commonly expressed in terms of the pH scale

60. Enzymes in Biotechnology How does pectinase work?

61. Pectin is the cement that holds plant cells together. Pectinase helps farmers break down the plant cells faster. For example it might help a farmer release the juice from apples faster to make lots of Apple Juice. Pectin is the cement that holds plant cells together. Pectinase helps farmers break down the plant cells faster. For example it might help a farmer release the juice from apples faster to make lots of Apple Juice.

62. Other enzymes in biotechnology… Biological washing powder Biological washing powder Meat tenderizer Meat tenderizer Production of glucose syrup Production of glucose syrup

63. Enzymes Everywhere